The Moon Was a Witness
by Sonorous Scripter
Summary: After being caught in the Restricted Section of the Library, Stiles winds up serving detention with seventh-year Derek Hale. Side plot where a series of murders occur within the school, the only common link being their bloodied, mangled mouths and lack of teeth. Hogwarts AU
1. Chapter 1

Stiles' long, deft fingers continued to tap an arrhythmic beat on the hardwood desk, the dull sound reverberating through the dungeon. God, he could practically feel the layers of dust coating the insides of his nostrils. Didn't Harris ever clean his classroom? The miasma of burnt plastic lingered in the air; evidence of potion assignments gone wrong. To be fair, Stiles could be partially credited as the cause of the smell, but if his potions possessed explosive tendencies, then that was more of a reflection on Professor Harris' inadequate teaching skills.

"Dude," Scott hissed, "that's really distracting."

Stiles quirked an eyebrow, and Scott nodded at his hands, which were still tapping, as if they had a mind of their own. Sighing inwardly, Stiles forced his hands to still, but his foot began tapping to compensate. Around him, students were scrawling away on their parchment paper, brandishing their quills, and looking as bored as he was. Stiles' paper was painfully blank, the only spots of color being from the steady drip of ink off the end of his quill. The ink was red, and not unlike blood. Stiles bit his cheek, thinking back to the previous evening.

_"See?" There had been a concerned undertone to Derek's voice. Derek. As in, Derek Hale. Derek freaking Hale, who until last night, hadn't even known Stiles existed._

_"Yeah, uh, that would be a book."_

_"It's written in blood."_

_"No, I'm pretty sure that's ink."_

_In response, Derek had made a low noise in the back of his throat, that sounded almost like a growl. "It's a summoning book. Extremely rare, written in demon blood, and deadly in the wrong hands."_

_"Wow, uh, good thing they're in your hands. I mean, it's in your hands. Since there's only one. Book, I mean, not hands. Obviously you have more than one hand. Hey, uh, nice hands, by the way." _

_"There are pages missing." Derek flipped through the book, indicating where several pages had been messily torn out. _

_"And that's bad?" Stiles asked. Derek suddenly went ramrod straight, and Stiles could see the tautness in his muscles from where he was suddenly gripping the book. _

_"For you two," a voice said from behind—a voice Stiles was, unfortunately, very familiar with— "I'm afraid it is." _

"Hey, Stilinski," Stiles looked up sharply to see Jackson Whittemore leveling him with a smirk. "Taking out your sexual frustration on your homework?"

Why did potions have to be with the Slytherins? It was already the worst class. Though, to be fair, Stiles had practically stabbed a hole through his parchment. What could he say? The red ink reminded him of blood, so naturally he pretended that his paper was Harris' face. Which is why he was stabbing it. Repeatedly.

"Yeah, well, we all have to take our frustration out somehow. How do you get rid of yours? Sucking up to Lydia, or falling off your broom during Quidditch?"

A few other Slytherins looked up, and Stiles felt Erica's gaze turn towards him, too. Unlike the rest of her house, though, she simply looked amused, as if she were reveling in their argument.

"Good one," Jackson said, his eyes narrowing into slits, "maybe you'll have time to think up an even better insult during your detention. What is it, like an extra hour with Harris? Or two? And on a Friday."

Stiles bit back a retort. How had Jackson even found out about it? Scott was the only one who knew Stiles had been in the restricted section of the library… well, besides Derek Hale. If Jackson knew about his detention, then chances were he knew that he'd be spending it with Derek. Stiles contemplated making a crack about how he was actually screwing the Slytherin prefect, because, okay, that wasn't actually true, but they'd been caught together and did Jackson really need to know the details? Before he could even open his mouth, Harris was swooping down on him like a hawk.

"Would you like to go for double detention, Mr. Stilinski? Or should I take another fifty points from your House?"

Stiles was silent for the rest of the class.

-x-

"For detention, the two of you will clean out every flask, vial, and beaker, scrub the cauldrons, sort through the potion ingredients and reshelve the extra potions books. When I get back the two of you better still be here, and all potions ingredients must be accounted for."

"Wai-wha? Why do you get to leave?" Stiles sputtered. Derek turned to him with a glare, as if this whole thing was his fault. It wasn't. Derek had been in the restricted section of the library before he'd even gotten there.

Harris raised an eyebrow. "I'm not the one serving detention. And next week is Halloween. The house elves are all ready bringing out themed food. I'm sure you two won't mind settling for leftovers, once you're done. Oh, and, wands, so I know you two won't use any magical means to finish your detention early." He held out a hand expectantly.

Stiles made a mental note to tell Scott to buy him a wand cleaning kit for Christmas, because there was no way he was going to use it after Harris' hands had touched it. Begrudgingly, he handed it over, watching Derek do the same. Derek had been silent thus far, but from the clench in his jaw, Stiles could tell he was practically livid.

"You know, back in third year," Stiles began, as soon as Harris had left, "I came up with a plan to kill him. I had concise notes and everything, narrowed it down to what time he'd be alone, and even had the incantation to several killing spells. Silent ones, too, so no one would know I was the caster. Professor Deaton heard me and Scott talking about it once. He said I'd make a good serial killer. Or a Ravenclaw."

Derek was silent but the faintest trace of a smile hinted at the corner of his lips. Or a smirk. It was probably a smirk. And he probably thought Stiles was an idiot. If that was the case, then he was right. Stiles was pretty sure the rest of detention was going to be spent in silence, when Derek spoke up, "Why aren't you in Ravenclaw? Professor Yukimura said you wrote a five page essay on the mating rituals of centaurs. He sounded pretty impressed."

"You asked about me?" The surprise was clear in his tone.

Derek scowled. "He told our whole class about your essay. Like last year, or something."

"And you remembered my name?"

"Stiles Stilinski. That's not the kind of name you forget easily."

Stiles nodded, before returning to the assortment of beakers that needed to be cleaned. He couldn't bring himself to fight the smile off his face.

"That and I asked that Whittemore kid who you were."

"You _what?_"

Derek's eyebrows furrowed. "I've seen you two talking before. Aren't you friends?"

"No!" Stiles exclaimed, before groaning, "Well, I don't have to ask why _you're_ not in Ravenclaw. That explains how he knew about my detention. Seriously though, no one likes him. Lydia and him have been dating off and on, and _she_ doesn't even like him. Actually, I'm pretty sure Jackson doesn't like Jackson."

"Lydia? She's that fifth year Ravenclaw, right?" Derek sounded disinterested, but maybe he just wants to keep up conversation to pass the time.

Stiles nodded. "Yep, top of the class, five foot three, hazel eyes, perfect strawberry blonde hair. Oh, hey, how big is yours?"

"What?" Derek blanched at his words, his hands freezing over the cauldron he was currently scrubbing. Some kind of fetid residue was stuck to the bottom.

"Your wand. You know, the one Harris just took. How big is it?"

"Uh, eleven inches," Derek's gaze was back on his cauldron.

"Ha! Mine's bigger! What type of wood is it?"

"Hornbeam."

"Hornbeam wood is supposed to be stubborn, right? Totally suits you! Mine is Aspen. Defiant and talkative."

Derek made no sign that he'd been listening to what Stiles had just said, but he muttered something distinctly like, "Talkative? That can't be right."

Stiles just smiled to himself again, before realizing that he had just re-scrubbed the same vial for the fourth time. It wasn't his fault that Derek was so distracting. The guy looked like he took daily doses of beauty potion. He had a jawline sharp enough to cut paper, prominent cheek bones, and supple lips. Not to mention his body. He was also a Slytherin prefect. And a seventh year. Who would definitely not show any interest in some gangling fifth-year. Stiles had known who Derek Hale was practically since coming to Hogwarts. Half the school's population was crushing on him, but besides briefly hooking up with Kate Argent several years ago, the guy had remained single.

Huh. Thinking back, Stiles realized that he still hadn't deduced what had happened to Kate Argent. She'd been a popular Slytherin, before being expelled. Her older brother, Chris Argent, was the Defense Against the Dark Arts teacher, her father was the Headmaster, and her niece, Allison, had served as Scott's first crush way back when. Stiles was just about to ask, when a high-pitched scream pierced the air, slicing through the silence like a knife.

Derek and Stiles jumped to their feet. "Who—?"

"Lydia," Stiles said thickly, "that sounds like Lydia."

Technically, Harris had said to stay put, but generally, when you hear someone screaming their lungs out, staying put is the worst thing to do. And Stiles hadn't really intended on being confined to the potions room all evening, anyways.

When they found her, she was hunched over in the adjacent room, her liquid eyes brimming with tears, and her make-up smudged in a very non-Lydia way. Stiles stole a glance at Derek, whose eyes were practically glowing blue in the torchlight. What color were they normally, anyway? Stiles made a note to find out later.

"Hey, Lydia, are you okay?"

"I don't know what happened," she said in a tremulous voice, her hands securing themselves on either side of a desk, "but I started hearing things. I was in the Great Hall, and when I took a sip of my drink, it tasted like blood."

"Blood?" Stiles stomach roiled with nausea at the thought.

"Blood," she confirmed, "like copper, and then the voice got louder and I... I think there's a body."

"A body?" Stiles repeated. The room was dim, but clearly not vacated, save for themselves.

"Yes, Stiles, a body."

"Well, I see three bodies, including mine, but all of them are very much alive. Derek may look kind of dead, but he has a naturally empty and bored default expression, so..."

"No," Derek murmured. "She's right. Something smells... off."

"That would most likely be the smell of a foot fungus potion, which I was cleaning off one of the vials."

Ignoring him, Derek edged further into the room. "Do you have a wand?" he asked, directing the question towards Lydia.

"No, my parents were too poor to buy me one," she snapped, but handed it over regardless. 10¼ inches. Rosewood. Veela hair. Stiles probably shouldn't know that, but he'd been enamored with Lydia since first-year when she'd shown him how to properly hold his wand.

"Lumos," Derek whispered softly, and Stiles definitely didn't gulp at hearing that tone of voice. And it definitely wasn't like velvet to the ears. And he definitely wasn't imagining Derek saying other things in that low, hushed tone.

The room was small, probably an abandoned classroom, or just a place to store desks. There wasn't, however, really any room to store a dead body. On account of all the piles of desks. Stiles walked a few paces behind Derek, turning to search through a different aisle, when he face planted with an indignant cry. He'd tripped over something. Something that felt oddly like... "Oh god!"

"Is that...?" Lydia's arms were clenched tightly across her chest.

"An invisibility cloak," Derek confirmed, pulling the thin fabric away with a flourish. It was a girl's body. Her yellow and black tie was stained red with dried blood. Blood that seemed to have come from her mouth.

"Who is she?" Derek asked, not tearing his eyes from the body.

"I don't know," Lydia said slowly. "She can't be much older than us. I-I'll ask Allison, she's in Hufflepuff. She'll know."

"Ask Allison?" Stiles echoed. "Ask a teacher! Why are we just standing here?"

"She's already dead, Stiles. It's not like there's a rush." Derek still wasn't making eye contact but their was a definite strain to his voice.

Lydia's high heeled shoes applauded her exit as she ran through the corridor without another word. Derek tilted the girl's face, before prodding her mouth open.

"What killed her?" Stiles muttered, his chest feeling a lot tighter than it had minutes ago. "And why? Who would want a student dead?"

"I think I know the 'why' part, at least. Look."

Stiles did, following Derek's gaze. Her mouth was bloody and mangled, the gums torn, and extremely lacking in the department of teeth. Stiles shuddered as Derek continued to examine her. There was a lull in the conversation, but the silence was charged with tension. Stiles was used to barreling through silences by talking. It felt natural to do so now.

"Do you think it was a dentist that killed her?"

"A what?"

"Sorry, it's a, uh, muggle profession. Oh! It could've been a wizard dentist!"

"Stilinski! Hale! I thought I told you not to leave the room."

Stiles and Derek winced, before turning to face Professor Harris, who did a double-take at the sight of the dead girl. "You know," he said slowly, his voice like acid, "I half suspected that you two would strangle each other before the detention was over, and I would, in fact, be completely willing to overlook one of _your _deaths. But killing another student," he removed his glasses to wipe off a smear.

"It wasn't us," Derek said slowly, "we found her like that."

"Well, actually Lydia found her. And we found Lydia. Screaming. Though, mind you, I'm the one who tripped over the body, so I guess I was really the one to find her..."

"Save it, Stilinski. That was sarcasm." Right. Sarcasm delivered in a deadpan voice. "I already know you're not capable of pulling off murder. But we'll see if the Headmaster thinks as much. Oh, and, the two of you have detention for the rest of the week. Should we say, ten points from Slytherin and Gryffindor? Or how about another fifty?"

"What's going on here?"

Stiles prayed silently that Harris would give him his wand back, if only so he could use the killing curse on himself. The Headmaster stood with Deaton and Lydia behind him.

"Headmaster, these two were caught murdering another student."

"What?" Stiles gawked. Was Harris for real? He turned to Derek, but he was his usual silent self.

"Is that so?" Gerard eyed them suspiciously. Lydia stood a few paces behind him, her hands still trembling slightly. This was Gerard's first year as Headmaster, and Stiles could honestly say that, two months into school, he already hated the guy. "And just what spell did you two cast?"

"We couldn't have cast anything, Headmaster. Harris confiscated our wands during detention. And this body has evidently been here for a while," Derek said, with a politeness Stiles hadn't before witnessed.

Gerard nodded, as if silently agreeing with Derek. Professor Deaton stepped forward, before stooping to examine the girl. "Her teeth have been removed. By force, obviously."

"Have you seen cases of this before?" Gerard inquired.

"Personally? No. But it's not unheard of. Just not a particularly common practice. Should we say, ten points to Gryffindor, Ravenclaw, and Slytherin?"

"What?" Harris sounded crestfallen. "But these two were supposed to be in detention. They disobeyed my direct orders."

Deaton gave a noncommittal "Hmm. Ten points to Ravenclaw, then, and five to both Slytherin and Gryffindor. Now I think it best if the three of you," He nodded to Lydia, Stiles, and Derek, "left."

"A visit to my office for questioning may be necessary, later on, though," Gerard interjected.

Stiles was about to protest, but Derek answered, "Thank you, Headmaster," without missing a beat. After getting their wands back, they headed out the door. Once out of earshot, Stiles grabbed Derek's arm.

"You know something, don't you? About the teeth? You and Deaton had the same look on your faces. It's something bad, isn't it?"

"It's late," Derek replied curtly. "You two should head back to your dormitories."

"If you know something-" Lydia started.

"If I know something, I'll report it to the Headmaster. You two really should leave. I am a prefect and I can take points away from your Houses if it comes to it."

Scowling, Lydia stalked off. Stiles turned to leave too. Once he'd reached the end of the corridor, he risked a look back, expecting Derek to be long gone. Instead, he was staring in Stiles' direction, frowning. Derek ducked his head immediately, gaze instantly hardening, before leaving for the Slytherin common room in the opposite direction. Stiles smiled at Derek's retreating form, partly because he had another detention with him, and that was plenty of time to convince him to talk about the teeth, and partly because it wasn't a bad view.

* * *

><p><strong>Author's Note: You can also find this fanfic on Archive of Our Own, because that website doesn't glitch every time I try to post a new story :P Anyways, thanks for reading! Reviews and feedback are always appreciated.<br>**


	2. Chapter 2

The morning sun bathed Hogwarts with a soft dawn light, spilling over the vast expanse of craggy hills and verdant fields. There was a kind of stillness to the air from so high up and at so early in the morning. Though that particular peacefulness couldn't be known for its longevity with Finstock as the Flying Instructor.  
>"Pathetic! Unbelievably pathetic! What, are you training for ballet?"<p>

"Coach," Scott called, veering his broomstick downwards. "Are you sure this is the kind of pep talk we need right now?"

"You just worry about catching the snitch, McCall. I was trying to offer you guys a few pointers, to save you the embarrassment of getting slaughtered by Ravenclaw."

"It's only our second practice. And the game isn't for, like, a month."

"Hey, the Headmaster was the one who made it mandatory for a teacher to be present during Quidditch practice… After recent incidents, thank you, Greenberg. How do you even manage to hit yourself with a Beater's bat?" Striding away from Scott, Coach Finstock cried out, "Jared! Airsick, again? How did you even make the team?"

"Hey, Scott," Stiles called, diving to meet him. Stiles' movements on a broom weren't as clean or practiced as Scott's but he'd managed to make the cut for second line-up. "Want to try being Keeper so I can take a few shots?"

"Uh, sure," Scott said, though his warm brown eyes were fixated on some vantage point over Stiles' shoulder. "But I think it'll have to wait. Harris is coming over and he looks pretty—"

"—Oh no. Is here for real?" Stiles slumped forward on his broom, while locking eyes with the potions master. Scowling with a frown that would rival Derek's signature look, Stiles landed on ground, though not as gracefully as he would've liked.

"Adrian!" Finstock cried enthusiastically, waving his fellow colleague over. "Didn't know you were a fan of the art that we call Quidditch."

"Actually, I'm here to talk to one of my students."

"Is it Greenberg? Man, I don't know what that kid's problem is."

"Stilinski, actually." Harris' voice was clipped and carefully measured, and if Stiles had any common sense, he'd use his broomstick to fly far, far away. Instead he meandered closer towards him, biting back several curses. The rest of the Gryffindor Quidditch team was present, and if Harris murdered him, at least he'd have eye witnesses that would help his father, who happened to be Head of the Department of Magical Law Enforcement, send Harris straight to Azkaban. "Come with me, please."

"Professor, is this about the dead body we found? Because I was kind of in the middle of a practice, so if we could make this quick—"

"Quiet."

"Yea…kay. Quiet. I can do that."

"Don't think I don't know what you and Hale were up to."

Stiles' mouth fell open in surprise because, honestly, he didn't even know what they'd been 'up to'.

"Syrup of Hellebore, crushed Wolfsbane, both missing from my potions cupboards. Don't let me catch either of you stealing from me again."

Wait, what? Stiles opened his mouth to protest, but Harris was already walking away. "Oh, and after dinner, meet me outside the Forbidden Forest. You'll be serving detention elsewhere today."

-x-

Rather than heading back to the Quidditch pitch, Stiles decided to spend the rest of his morning at the library (after retrieving his school bag, that is). Might as well catch up on his homework while he had the chance. Getting lectured by Harris before noon had been enough to ruin his Saturday, but with detention hanging over his head, he knew things were only going to get worse.

The musty scent of old paper permeated through the air, and Stiles inhaled deeply as he walked through the doors. The library was almost completely deserted, aside from the odd student. Stiles settled down into a chair, before opening his Ancient Runes text book. He honestly had no idea why he was even taking the class. Professor Morrell definitely didn't make it an easy one to pass. It was kind of interesting, though. Or it would be, if Stiles was better at focusing.

He managed to transcribe about a half a page, before he froze. One of the symbols looked strangely familiar. It was a kind of swirl shape, branching off into three different sections. The book he and Derek had been looking at before getting caught by Harris had had the exact rune. Half of the text had been written in Latin, or some other dead language Stiles didn't recognize, but there had been a number of elaborate runes marking the pages.

Easing into a standing position, which wasn't that easy with all of his bulky Quidditch gear, Stiles began leafing through some old books, searching for any available to students that contained information on runes. He wandered up and down a few aisles,before hesitating. The low rumble of voices carried from past the shelf he was currently facing. He tilted his head forwards. The timbre of the first voice was soft, yet deep, and the second voice was distinctly feminine.

"Are you sure you didn't just lose it?"

"I never took it out of my bag. Someone stole it."

"No offense, Erica," a third voice cut in, "but why exactly did you have a concealment charm on the inside of your bag in the first place?"

"Well," she hissed, "if people go through my bag, I don't exactly want them finding my feminine stuff, now do I?"

"Fair enough."

"If it was invisible, how do you know it wasn't stolen a while ago?"

Stiles shifted one of the books on the shelf over, peaking through the thin space to make out Erica, Boyd, and Isaac. Erica's eyes were fringed with mascara, and she and Boyd had traded their robes for Muggle clothes. Isaac was still wearing his Hufflepuff robes, which, after his recent growth spurt, barely extended to his ankles.

"I don't know," Erica conceded, "but it was a family heirloom and I need it back." Boyd's expression softened, but Isaac still looked confused.

"I really don't get why anyone would steal a bracelet of teeth."

A sound of surprise slipped from Stiles' throat, and Erica, Boyd, and Isaac turned sharply to face him. His cheeks suffused with color at being caught so blatantly eavesdropping, but Erica only smiled, her bright red lips curving upwards.

"Hello, Stiles."

He flailed a bit before responding. "Uh, hey, Erica. Boyd. Isaac."

"How was detention with your... monosyllabic boyfriend?" Erica asked casually.

Stiles swallowed thickly, willing his voice to sound level. The last thing he needed was giving Erica Reyes more ammunition. "Oh, well, you know Derek, always talking up a storm."

"Right," she smirked. "So what brings you to the library this early?"

"Oh, just picking out a book for some light reading."

She nodded seriously, a stray blonde curl falling farther into her face. "Here's a book," she said, pulling a random one off the shelf. "Enjoy."

"Thanks," Stiles said with forced cheeriness, reaching a hand through the book shelf to accept the leather-bound book as a placating gesture. Erica leaned in, dangerously close to his ear, and he felt his pulse stutter. Erica was a Slytherin after all, and they had a reputation for being ruthless.

"Since you kind of owe me," she whispered, her lips barely moving, "take Isaac with you. He's kind of being the third-wheel."

Stiles blinked in surprise, and Erica seemed to savor his bemused reaction. "Uh, right. Hey, Isaac?" he fumbled for words, "Want to hang out for a bit?"

"Is Scott going to be around?" Isaac asked.

"Nah, he's still at Quidditch practice. And he usually takes a shower after that."

"Right, shower," Isaac nodded, "are you going to take one too?"

Stiles' eyebrows jumped. He wasn't sure where this was going.

"Because no offense, but you, uh, you kind of smell."

-x-

Stiles meandered through the corridor, eyes set on the Great Hall. From where he stood outside, he could already see floating jack-o-lanterns and decorations suspended from the high-vaulted ceiling. Cobwebs tangled around looming pillars, and ghosts flitted about, some engaged in conversation with the students, while others just wandered aimlessly. The lighting was dim, but the ceiling reflected the sky, which was currently a uniform pink receding into a darkening blue. Sunset was easily his favorite time of day, and the gold-pink hue of the sky enveloped the room in a gauzy aura.

Stiles maneuvered his way around a trio of dancing skeletons, and only stumbled twice as headed for the Gryffindor table. On Scott's right was an empty space, presumably for Stiles, and on his left was Isaac, who was sandwiched between Scott and Allison. The three of them were deep in conversation, and there was something both sad and fond to Scott's smile.

They hadn't noticed Stiles yet, and he was about to call out a greeting, when someone cut directly in front of him. That someone had a pained expression on his face, as if conversing with Stiles was a chore.

"We're going to the Forbidden Forest." Derek said gruffly, and Stiles barely heard him over the din of chattering voices and clanking cutlery.

Arching an eyebrow, he tried to side-step him. "I haven't eaten yet."

"You can eat when we get back."

"It's six O'clock! All the food will be gone."

"Then why weren't you here earlier?" Derek asked impatiently.

"I was taking a shower, and before that I was trying to get rid of Isaac."

Something almost imperceptible changed in Derek's expression, but the gaze he fixed Stiles next was withering. "We're going."

"Not before I eat something," Stiles protested, because he wasn't in Gryffindor for nothing. Just because Derek was older, and taller, and well built (and also really good looking), didn't mean Stiles was going to be intimidated.

"Here," Derek muttered with a resigned sigh, thrusting a napkin wrapped pumpkin pasty into his hands. "Now let's go."

"Can't. I'm allergic to pumpkin."

Derek squinted at him, as if to say 'who the hell is allergic to pumpkin?' Finally shaking his head, Derek affixed his hand to Stiles' shoulder, and forced him to follow. The sounds of bright laughter and chattering voices faded to a distant rumble, and the only sound that followed was the growling of Stiles' stomach.

Once outside, Derek narrowed his eyes, scrutinizing him. "What?" Stiles demanded. Wordlessly, Derek leaned forward, his thumb brushing the corner of Stiles' mouth and leaving a blazing trail of heat. Stiles froze. Derek's thumb was close enough to his mouth that if he licked his lip…

"Crumb," Derek said simply, and that single word was enough to snap him out of his stupor.

"Okay, fine, I'm not actually allergic to pumpkin. But this is the second time I've missed the Halloween feast and you still haven't explained why we have to go to detention early."

"It's a full moon tonight."

"So?"

"So, when has being out on a full moon ever been a good thing?"

Stiles rolled his eyes. "Don't tell me you're superstitious."

Derek didn't answer, and instead continued walking across the grounds. Much to his chagrin, Stiles felt his feet immediately follow Derek, drawn to him like a moth to a flame. Only when they reached the outskirts of the Forbidden Forest did Derek's footsteps falter. "Did Harris tell you what we'd be doing?"

"No," Stiles said slowly, "but he did chew me out with allegations that I stole Hellebore and Wolfsbane from the potions cabinet."

Derek's gaze widened at the revelation. "Wolfsbane," he murmured, before shaking his head. "Well, he told me. I'm looking for a body."

"Wha—another one?"

"When was the last time you saw the Groundskeeper?"

"Uh, I dunno, the guy's kind of a recluse."

"He's been missing for almost a month. A letter with his signature was sent to the Headmaster, explaining that he was taking a leave of absence."

Okaaay," Stiles said slowly, languidly, drawing the word out.

"All magic has a unique handprint, and the note 'he' gave hinted at traces of a forgery enchantment. And none of his stuff has left his house. It's like the guy got up and left all of his possessions. That or he was kidnapped."

Stiles' face scrunched up in confusion. "So, we're trying to find the dead body of a guy who may or may not be dead in the Forbidden Forest, of all places?"

"No. _I'm _looking for a dead body. _You_ are collecting knotgrass for our detention."

"What? Why do I have to?"

"Because I already have a rough idea of where the body could be. As a prefect, the teachers aren't as careful about gossiping around me."

"You know, Derek," Stiles said slowly, "I've had conversations with portraits that make more sense."

"Just follow me for now, and stick to the paths."

"Right, sure, follow the crazy dude who thinks there's a body out there. You know, Derek, just because you're attractive doesn't mean you're not secretly a psychopath."

"Shut up and walk."

Muttering to himself, Stiles reluctantly, albeit obediently, followed Derek. Dessicated leaves crackled underfoot as they walked. The trees began to grow thicker, blotting out the last remaining rays of sun, and forcing them to continue on through the perpetual gloom.

Stiles' wand protruded from the sleeve of his cloak, and with a whisper of, "lumos," there was enough light for them to see. The walk was long, and quiet, and Stiles tried to grasp at something to break the silence. Finally he just sighed, "did you figure out anything else about the teeth?"

Derek hesitated. "No."

"Too bad. Because I found something else out."

"Oh?" Stiles couldn't see Derek's expression, but he had a feeling the guy was just humoring him.

Stiles considered withholding the small piece of information he'd gathered, but he wasn't one to keep things to himself. "Someone stole a bracelet from Erica's schoolbag. A bracelet made of teeth." This, apparently, was enough to gain Derek's attention, because he whirled around so fast Stiles was surprised he didn't get whiplash.

"Who stole it? And when?"

"See, if I knew that, I wouldn't be bothering to tell you right now, but I don't know, and it would be a hell of a lot easier to figure out if you'd share what you know."

Derek grunted, and Stiles was just about to give up, when he started speaking, low, and quiet, as if one of the trees was suddenly going to eavesdrop. "That book I found in the restricted section of the library... It was a summoning book. Capable of invoking the powers of daemonic entities and hell spirits. I'm not good at reading archaic Latin, but I did recognize the word for tooth in there. It just doesn't seem like a coincidence. Someone steals a few pages from it, and suddenly people are being killed for their teeth."

Stiles bit the inside of his cheek. "I'm not sure how to figure out who's behind the murders, but I do know someone who can read archaic Latin."

"Really?"

Stiles felt just a bit smug as he nodded. "Lydia Martin."

Rather than looking relieved, Derek's face contorted into a scowl. "You stay here. There's a patch of knotgrass up ahead. I'll meet you back a bit later." Stiles started to protest, but Derek had already turned to leave. Muttering to himself, Stiles began gathering knotgrass. It was slow, tedious work and he wasn't sure exactly how much Harris wanted, so he figured he might as well collect all of it from this particular patch. Sweat began pooling along his pack, but when Stiles tried to wipe his sweaty palms on his robes, they slid right off, failing to absorb anything. The temperature was starting to drop, he could see faint streams of moonlight filtering in through the canopy of trees. Derek still wasn't back, but he wasn't going to wait around all night. Rising to his feet, and tucking a bushel of knotgrass under each arm, Stiles hesitated. He was a few feet away from the main dirt path, but something didn't feel right. There were all kinds of creatures residing in the Forbidden Forest. Derek might've become werewolf chow by now. Or trampled by a centaur. Or made a nice drink for a vampire. Or any other number of possibilities. Sighing inwardly, Stiles used the four pointer spell to locate Derek.

When he finally found Derek, he felt partial relief that he had not, in fact, been trampled by a centaur. A face that perfect did not deserve to be trampled. On the other hand, Derek was hunched against a tree, his breathing ragged.

"Uh... Derek?"

"Lost track of time. Head back without me."

"Dude, are you sure?"

"Just go!"

Nodding slowly, Stiles turned to leave. He would have, too, if not for the gasp Derek let out. He swallowed thickly, because that was a sound he wouldn't mind hearing again. Risking a glance at Derek, Stiles' amber eyes met a bright, glowing blue. So not a trick of the light. Since there weren't any torches or lamplights that could be giving that effect. Just Derek's eyes. Which were blue. A brilliant, scintillating blue.  
>For a brief moment, Derek just stared into Stiles' eyes; and his gaze was unforgiving. And then he shook his head, and choked a gasp of "run."<p>

Stiles didn't run, not at first. Because Derek was evidently in pain, but his limbs were starting to elongate, and his mouth was forming a snout, and oh god, he didn't look like a cuddly puppy anymore; he looked like a vicious wolf that was planning on tearing Stiles apart without a second thought. Stiles thought distantly of how Derek had cringed when he'd said that Wolfsbane from Harris' cupboard had been stolen, and back to the restricted section of the library, their first real encounter, when he'd glared accusingly at Stiles. The reason Stiles had snuck in was because he'd promised to retrieve a lycanthropy book for Scott. As soon as Derek had seen Stiles with the book in hand, he'd glared, as if Stiles has personally offended him. Attending school with a murderer lurking about was one thing, but being in love with a werewolf was another. He was so dead. Possibly literally. Hopefully just metaphorically, though.


End file.
